Oil smoke generator



J. TWEEDDALE OIL SMOKE GENERATOR Filed July 8, 1942 2 Sheets-Sheet l Joim fwazzaz Patented July 3, 1945 2,379,766. KE GENERATOR w John lT-weeddale Tormfice, Calif."

. v Application July 8, 1942, Serial No.

1 Claim. (01. isa-+91) This invention relates to an oil smoke generator designed to provide maximum smoke for smoke-screen purposes in warfare, to combat frost in citrus fruit grooves or the like.

It is especially aimed to provide a generator or smoke producer wherein maximum productionof smoke from oil is realized, wherein the smoke "will ascend without movement toward the center of the apparatus, wherein anti-flare or blackout shield means are provided, wherein draft regulation is afforded and wherein the parts maybe separated to occupy minimum space in storage or transportation. l

The more specific objects and advantages of the invention will become apparent from a consideration of the description following taken in connection wit-h accompanying drawings illustrating' an operative embodiment.

In said drawings: Figure lis a view in side elevation of the apparatus;

Figure 2 is a vertical sectional view on an enlarged scale, partly broken away, taken on the plane of line 22 of Figure 1;

Figure 3 is a horizontal section taken on the line 3-3 of Figure2;

, Figure 4 is a horizontal section taken on the line 4-4 of Figure 2; l t

Figure 5 is an inverted plan view of the antiflare or blackout shield; Figure 6 is a plan view of the downdraft anti fiare shield; l

Figure 7 is a cross section taken on the line 1-1 of Figure 2.

Referring specifically to the drawings wherein like, reference characters designate like or similar parts, Ill designates a reservoir for oil which may be supplied through an opening closed by a screw plug 5 I. The side wall of reservoir l preferably inclines outwardly at a slight anglein upward direction andat the upper edge thereof a convex cover I2 is secured, the same having a return flange or bead 13' at its lower edge.

A smoke emitting stack M of tubular form and tapered with its smaller end lowermost is de tachably and frictionally engaged over an upwardly flaring collar l provided centrally of the cover l2.

A downdraft tube [6 is disposed within reser-,

voir Ill, being secured. at ll to the cover l2. Such tube is tapered with its smaller end lowermost and open and such tube has longitudinallly ex-.

tending openings I8 provided therein communicating with the interior of the reservoir. H1, in order to supply air for combustion of the oil in the reservoir. The oil and air mixture in the reservoir, may be ignited in any suitable way, for instance by a standard modeltorch or by the remote control electrical devicedisclosedin my co-pending application, Serial No. 3l1,5 49.

An anti-flare shield l9 consisting of a conduit or tube and an inclined top 2|, is frictionally shield and are bolted as at 30 to the upper end and .detachably telescoped over an extension or collar 22, formed at the upper end of the downdraft tube [6 and extending above the cover.

An air inlet opening 23 is provided in the shield. at the duct 2|] and such opening may bewentirely closed or partially closed to regulateinlet of air, by manipulation of a vertically slidable plate or closure 24, preferably of arcuate form, engaged in an arcuate slot 25 of the top 2|, it being clear. that the sliding fit of'the closure 24 in slot 25 is such that sufficient friction exists between the top and the closure to hold the latter in different adjusted positions. vided on the closure. It will also be noted that the top 2| is preferably relatively large and extends outwardly around the conduit or tube 20, for anti-flare and blackout purposes.

Over the stack 14,1 provide an anti-flare or blackout shield 26 whose main wall is convex at the lower surface. Extending from such surface;

is a central ring or flangeZ'l and marginally of the main wall of shield 26, aflange 218 extends upwardly. A series of legs 29. depend from the of the stack, to secure the shield at any desired distance from the outlet of the stack, usually four inches or more. 7

I have found that maximum production of smoke cannot be obtained from the combustion of oil with a generator unless all of the parts of the latter are properly designed in proportion to each other and which proportions are only ascertained through much experiment and use.

Unless such proportions are. proper the color. and

weight of the smoke produced by the generator will not be satisfactory for screening purposes,

" nor will its volume be sufficient to make the deone-quarter inches in diameter. proportion of all other parts can be figured from vice practicalbecause a considerable part of the smoke will be consumed by flame at the base of thestack. The proportions used in the instant device enable it to produce a larger volume of smoke than any device of its nature heretofore constructed. The present generator has been actually built and operated and I preferto build it with the base of the reservoir twenty-three and The size and such dimensions. I have found that the fuel in A handle 25 may be pro-.

the reservoir will ignite instantly and will burn without attention until exhausted.

The concave shape of the shield 26 is important. The rim 28 causes the smoke to ascend vertically marginally of the shield rather than to curve over the shield and toward the center and reduce the diameter of the column of produced smoke. The ring 2'! acts as a draft regulator in conjunctiongwith the convex curve of the shield and is instrumental'in increasingthe-smoke outi moved to closed position will excludevairqand serve to extinguish the flame to stop the burning of the oil. Y

As stated, various parts of the inventionmaybe separated to occupy minimum space in shipmen or storage.

Various changes may be resorted to provided they fall within the spirit and scope of the invention. a

I claim as my invention: A device of the class described having a reservoir and a stack leading therefrom, a cover on and provided with aninlet opening, said shield comprising a conduit, and the downdraft tube having an upward extension forming a collar "telescopically engaged by the conduit, a top on saidlcon'duit relatively large with respect thereto for blackout and anti-flare purposes, said top "havingia slot therein, and a closure movably mounted-in'said' slot and slidable across said opening.

JOHN 'IWEEDDALE. 

